Below script will helps us on how to create single lookup and multi lookup fields in SharePoint using PowerShell. please refer my previous posts on below scenarios:
- Create a new list in SharePoint using powershell?
- Check whether the list exits or not?
- Create a new field in SharePoint list using powershell
- Add items to the list in SharePoint using powershell?
- Create single lookup field in SharePoint using powershell?
- Create multi lookup field in SharePoint using powershell?